Technical Field
The invention relates to automatic car washes. More particularly, embodiments of the invention relate to operation and maintenance of mitters within automatic car washes.
Discussion of Art
Mechanized or automatic car washes are well known for cleaning the exteriors of automotive vehicles. Typically, an automatic car wash consists of a tunnel housing a variety of water jet stations and moving brush stations, through which a vehicle is pulled on a conveyor.
For example, as shown at FIG. 1, a vehicle 10 may enter a car wash through a mitter station 12. The mitter station includes a motorized rack 14, which drives numerous mitters 16 in oscillating motion lateral to the path of the vehicle. The mitters are long vertical swaths of fabric that rub against an exterior of the vehicle, subsequent or concurrent with application of sprays or jets of water and/or chemicals, thereby removing grime from the vehicle exterior along with most of the water and/or chemicals. In order to accomplish their purpose of grime removal and toweling-off, formerly accomplished by manual laborers using terry cloth mitts (thus the term “mitters”), the mitters 16 are fabricated from porous and absorbent non-woven material. For example, a polyester/polyethylene nonwoven fabric is commonly used.
After passing the mitters 16, the vehicle 10 moves through a wraparound station 18 (shown in FIG. 2), where a set of rotating brushes 20 move around the vehicle on another motorized rack 22. The rotating brushes are driven by vertical-axis motors 24, which in turn move along rails of the rack. The rotating brushes typically comprise numerous long, thin strips of polymer (e.g., closed-cell foam) or other non-absorbent material. Typically, the rotating brushes are applied to the vehicle exterior in conjunction with additional sprays or jets of water and/or chemicals. One purpose of the wraparound station is to remove dust that may have adhered through the mitter station 12. Another purpose is to apply surface treatments such as wax, conditioner, coat sealer, polish, etc. The non-absorbent and smooth surface of the rotating brush strips enhances surface finish.
After the wraparound station 18, the vehicle 10 typically passes through an exit mitter station (not shown) that includes additional mitters. Here, the purpose of the mitters is to remove excess surface treatments and water. Again, the absorbent structure of the mitters aids in this purpose.
Thus, by the end of day down at the car wash, the mitters have become sodden with mud (at the entrance station) or with wax and conditioner (at the exit station). If the mud and wax (collectively, “build-up”) are not removed, then the mitters soon will begin to leave streaks on the vehicle exteriors, a problem resented by most people willing to pay for a car wash.
Accordingly, it is desirable to cleanse the mitters of their accumulated mud and wax deposits. One approach for cleansing mitters, often recommended by car wash equipment manufacturers, is to remove the mitters from their hanging racks and either wash them in an industrial laundry, or spray them down with a power washer (high pressure, high temperature water spray). However, it is not easy as a first step to remove the mitters from their racks. The porous nature of the mitters means that capillary action tends to draw liquid and grime throughout the mitters, and even into an upper edge of each mitter. At the upper edge a groove or C-channel formed on the hanging rack engages and supports each mitter. Liquid accumulated at this upper edge is difficult to extract (being somewhat trapped by the groove or C-channel) and makes the upper edge swell so that it requires brute strength to remove the mitter from the rack. Additionally, the process of laundering the mitters as a second step can take several hours, which means an additional shift of work after hours. Worse yet, industrial laundries are not reliably effective at removing build-up from mitters. On the other hand, power washing the mitters as a second step is not optimally effective due to the mitters flapping and twisting under impact of the power spray.
Therefore, a solution is desired for effectively cleansing mitters in place, without requiring removal of the mitters from their hanging racks; and, preferably, making use of the hanging racks to enhance efficiency of cleansing.